Friction shock-absorbing mechanism



Junell, 1929. J. F. OCONNOR FRICTION SHOCK ABSORBING MECHANISM Original Filed Fb. 8, 1923 Q\ f \N M w m d @N J R NNNNQU bw w 5 6 W Patented June 11, 1929.

.NITED' STATES PATENT OFFICE."

i image;

JOEN F. OCOLN'NOR, OF CHTOAGO, ILLINOIS, ASSI GNOE TO W. H. MINER, INCL, OF

CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE.

FRICTION SHOCK-ABSOR-BXNG MEOI-IAHISE'I.

Original application filed February 8, 1923, Serial No. 61 3895,

Divided and this application filed January 31, 1927. Serial No. 164,888. Renewed l lovember 19, 1928.

This invention relates to improvements in friction shock-absorbing mechanisms.

This application is a division of my'application Serialllo. 617,695 for friction shock absorbing mechanisms, filed February 8,

One object of the invention is to provide a friction shock absorbing mechanism, more particularly adapted for railway draft riggings, wherein is obtained high capacity due to relatively large frictional areas in combination with a differential wedge action.

Another object of the invention is to provide a mechanism of the character indicated, including duplicate front and rear combined follower and friction shells, a plurality of relatively movable friction plates arranged in two groups at opposite sides of the mechanism, wedge spreading means interposed between the two groups of plates at opposite ends of the mechanism, each spreading means including a wedge block and a pair of co-operating friction shoes engaging the plates, and a tapered frictionelement interposed between each group of plates and the corresponding friction surfaces of the front and rear shells.

Other objects and advantages of the inven tion will more fully and clearly appear from the description and claims hereinafter following.

In the drawing, forming a part of this specification, Figure 1 is a horizontal longitudinal sectional view of a portion of a railway draft rigging, showing my improvementsin connection therewith. Figure 2 is a vertical transverse sectional view correspond ing substantially to theline 2-2 of Figurel. Figure 3 is a broken elevational view of a tapered friction element employed in connection with my improved shock absorbing mechanism; and Figure dis a side elevational view, partly broken away,'of one of the friction plates of said mechanism.

In said drawings, 101O indicate channelshaped center or draft sills of a railway car under-frame, to the inner faces of which are secured front stop lugs 1111 and rear stop lugs 1212. The rear end portion of the drawbar is designated by 18, to which is con ncctcd a hooded yoke ii. The shock absorbing mechanism proper is disposed within the yoke, and the yoke and the parts tl'ierewithin are supported by the usual saddle plate.

My improved mechanism comprises broadly: Front and rear follower casings AA;

tom walls '1515, longitudinally extending spaced side walls 16-I6 and an outer transverse end wall 17. The end wall 17 of each casing A co-operates with the corresponding stop lugs on the draf sills in the manner of the usual follower. The side walls 16of each casing are'provided with longitudinally ex-' tendinginterior friction surfaces 1818. The friction surfaces 18 are inclined with respect to the longitudinal axis of the mechanism and converge toward the end wall of the casing.

Then the mechanism is in the full release position shown in Figure 1, the inner end of the front and rear casings A are spaced apart to such anoxtent that when the mechanism is fully compressed, the casings will abut, thereby acting as solid column load transmitting members to prevent undue compression of the main spring resistance G. I

The friction plates B are arranged in two groups at opposite sides of the mechanism,

each group preferably comprising six plates. The platesB are all of similar design, each being enlarged at one end thereof to provide top and bottom lugs 1919 adapted to cooperate with the spring followers F as hereinafter pointed out to effect restoration of the plates to normal position after each compression of the mechanism. The six platesof each group are so arranged that alternate plates have the ends bearing the lugs disposed at the same end of the mechanism. It will be evident that the platesof eachgroup are thus positioned, when restored by the spring followers so that the ends of the plates at the front and rear of the mechanism will be staggered. In the normal position of the parts, three alternate plates of each group have their front ends spaced from the end wall of the front casing hand the remaining three plates have their rear ends spaced from the end wall of the rear follower A. By this arrangement, it will be evidentthat upon relaof identical design.

tivc approach of the followers, during the initial action of too mechanism, there will be no relative movement of the plates, thereby providing; light frictional resistance. When the follower casings A have been moved rela- .sponding follower casing- A. Each wedge block C is also provided with a pair of wedge faces at opposite sides thereofadapted to cooperate with the fiiCLlOIl shoesD at the same end of the mechanism. The friction shoes D are arranged in two pairs atthe front and rear of the mechanism and co-operate'with Each friction shoe isprovidthe wedges Q. ed with an outer longitudinally disposedfiat friction surface Ehadaptcd to cooperate with the innermost friction plate Bat the same side of the mechanism. ()n the inner side, each friction shoe l: is providedwith 1a eral eularnemcntQd having wedge face 122 thereon correspondingly inclined to and adapted to co-operate with the wedge face 22 of the wedge block C.

The friction elements E are two in numher and are d posed at opposite sides oftho mechanism between the friction plates and the corrcspondin side walls ofthe casing A. Each of th friction elements E isin the form ofan elong .ted rectangular plate having an inner longitudinally disposed flat friction surface adapted to engage the outermost plate of the group B at the-corresponding side-of the mechanism. @11 the outer side, each frictionplate is provided with a pair of inclined'friction surfaces 26-26 disposed at opposite ends of thoplateand co-operating re spectively with the friction surfaces 18 of the front and rear casings A. At the opposite ends, .ach pl ateE-is enlarged to'provide top andihottom lugs 2727 adapted to co-operate with the frontan d rear springfollowersF to effect centering; oft-he. f 'iction elementsafter cachcounn'ession stroke-of the mechanism.

The spring-resistance G comprises an inner light coil and an outer heavier coil having their opposite ends hearing on the spring followers l? which are interposed between the spring; resistance and the enlargements 24: on the friction shoes D at the opgositeends of the mechanism.

The'spring followers F are inthe form platedike members having a pairof laterally projecting arms 28-28 at opposite sides thereof,the arms 28 of each pair being very tioal y spaced so astoaccommoeate themain body portion of thefriction plates B and the inns and the friction elements.

frictionelements E therebetween. The arms co-operate with the lugs 19 of the friction plates to effect restoration of the latter to normal posit-ion and also co-operate with the lugs Q'iat the opposite ends of the friction to the front and rear follower casings, the

head of the bolt being accommodated in the hollow boss 21 of the rear follower casing A and'the nut of the bolt being disposed witnin the hollow bos 21 of'the frontfollower casing. The retainer bolt not only servcsto maintain the parts assemblech-butalso maintains the same of overall.uniformlength and serves to hold the springs under a predetermined initial compression.

The operation of my improved shoe r ahsorbing; mechanism assuming a compression StlOlifl'lS as-follows: The follower casings A will be moved relativelytoward each-other, thereby carrying the wedge blocks C inwardly toward each other and setting up a wedging actionbetween the sameand the friction shoes D at the opposite ends of the mechanisn'n The friction shoes l) are thus forced apart, placing}; the friction plates of the two groups B under lateral compressions :forcingthe "111116 against the frictionelements R which are l'lGlCl'r Litil1St outward movement by the-side walls of the casings A. During the initial operation of the mechanism, there will he substantially no relative movement-of'the friction plates due .to theclearance existing between the outer ends of the plates and the end walls of the casing A. "When the clear ance between'the outer ends of the plates and the entlwalls of the casings has'heen taken up, the plates of each group will be forced to move relatively to each other in unison with the :follower casings A during the no mainder of the compression stroke of'the mechanism, thereby greatly augmentingthe resistance (iili'crecl. During the relative-"up preach of'the front and rear follower casings it, there will-also hea lateral l11\\2ll(lfil0-f0- ment of the friction elements l toward each other, due to the inclinationof the co-opcrating friction surfaces of'the follower cas- A differential action will thus he effected causing; the wedge friction shoes to slip inwardly on thc wedge faces of the wedgehloclts C, effecting additional compression of the main spring; resistance G. This ditferentialaction will occur throughoutithe period of relativesmovement of the casings A. Tlihe relative a5- proach'of the lasings A will continue either until the ,aetuatingforce is reduced or the inner ends of the casings come into engagement, whereupon the casings will limit the compression of the spring resistance G, the actuating force being transmitted directly through the casings to the draft sills, the casings thus acting as a column lead sustaining member as hereinbefore pointed out.

hen the actuating force is reduced, the expansive action of the spring G will effect release of the wedge friction system comprising the wedge blocks C and the shoes I). It will be evident that due to the initial movement of the casings A without movement of the friction plates, the arms 28 of thespring followers F will be moved away from the lugs 19 of the plates B and the lugs 27 of the friction elements E, thereby facilitating re lease of the mechanism by permitting outward movement of thefriction shoes D and wedge blocks C during initial releas with out effecting movement of the friction plates B. The arms 28 on the spring followers after the initial releasing action just described, will engage the lugs on the friction plates B, carrying the same outwardly and restoring them to the normal position illustrated in Figure 1. Due to the tapered construction of the friction elements E, and the fact that the friction surfaces of th casings A are inclined, the tendency during compression of the mechanism will be to n'iaintain the friction elements E in centered position. However, if these elements should become displaced during compression of the mecha ni'sm, restoration of the same to the normal position, which will be substantially that shown in Figure 1, will 'beassured by the arms 28 engaging the lugs 27 of the friction elements.

While I have hereinshown and described what I now consider the preferred manner of carrying out my invention, the-same is merelyjllustrative, and I conten'iplate all changes and modifications that come within the scope of the claims appended hereto.

I claim:

1. Ina friction shock absorbing mechanism, the combination with oppositely ar-.

ranged hollow front and rear follower casings provided with forwar lly and rearwardly converging friction surfaces on the interior thereof, said casings being normally spaced apart and adapted to move relatively to each other; of longitudinally arranged wedge-actuated lateral pressure creating means interposed between said followers at opposite ends of the mechanism, each of said means conr prising a wedge block movablewith the corresponding follower and a pair of frictionshoes co-operating with the wedge block; main spring resistance means interposed between the wedge actuated pressure-creating means; longitudinally arranged friction plates adapted for relative movement upon relative movement of the follower casings, said plates being divided into two groups at opposite sides of the friction shoes; and friction means interposed between each group of plates and the adjacent friction surfaces of said casings.

2. In a friction shock absorbing mechanism the combination with oppositely arranged hollow front and rear follower casings provided with interior friction surfaces converging toward the oppos te ends of the mechamsm of apan' of wedge blocks movable with said casings; front and rear sets of friction shoes co-operating with said wedge blocks; a plurality of relatively movable intercalated friction plates divided into two groups and disposed on opposite sides of the mechanism and co-operating with the friction shoes, said plates belng moved 1nwardly'relatively to each other upon relative approach positely disposed, longitudinally extending friction surfaces, inclined with respect to the longitudinal axis of the mechanism; a plurality of friction plates divided into two groups at opposite sides of the mechanism, said plates being adapted to be moved relatively'to each other upon relative movement of said follower casings; front and rear sets of friction shoes co-operating with saidgroups of plates; front and rear wedge blocks co-operating with the shoes and movable with the front and rear follower casings respectively spring resistance means opposing-relative movement of said front and rear sets of friction shoes; and longitudinally arranged friction elements having inclined friction surfaces co-operating with the friction surfaces of the front and rear follower casings, each of said elements having a friction surface co-operating withorie of said groups of friction plates. i

at. In a friction shock absorhingfmechanism, the combination with a plurality of groups ofintercala-ted friction plates, said plates being adapted for relative movement; of a wedge pressure creating means interposed fbetween said groups of plates,gsaid wedge pressure creating means'including front and rear sets of friction slices co-operatin gwith the friction plates and a wedgehlocl'r co-operating with eachset offriction shoes; front and rear follower casings cooperat ng with said wedge blocks and "adapted to ento move said friction plates relatively to each other upon relative approach of said followercasings, each of said followers being provided with longitudinally arranged fricmeans ell'ecting restoration of the friction ,plates'to normal position when the actuating force is reduced.

5. In a friction shoe-l: absorbing :mcchanisnn-the combination with a plurality of sets of relatively movable intercalated friction plates'di-vided lllljO two groups; 'of a front follower casing co-actingwith one set of plates of each groupto eliect'movement-thereof inwardly of the mechanism, said casing being provided with forwardlyconverging friction surfaces on the interior thereof; a rear follower casing co-acting with the other set of plates and provided ith rearwardly converging;- friction surfaces on the interior thereof; a friction element interposedbetween eachgronp of plates amlthe adjacent friction surfaces of said followers, said elementibeing provided with oppositely extendin; friction surfaces, one of said surfaces being arranged parallel'to andco-operating with one ofthe friction surfaces of the front follower and the-otherof said surfacesbeing arranged parallel to andco-operai'ing with one of the friction surfaces of said rear follower; front and rear pairs of friction shoes co-operating withsaid groups of plates; a wedge block cooperating with each pair of friction shoes; and s1, in resistance means interposed between said front and rear pairs of friction shoes, said spring resistance oppw-sing inward movement of the shoes, and the expansive action of said spring resistance elfecting restoration of the plates to'normal position when the actuating force is reduced.

6. In a friction shock absorbing mechanism, the combination with oppositely arranged front andrear follower casings provided with interior, inclined friction surfaces, said casings being normally spaced apart and adapted to vmove relatively; of wedge blocks movable with said casings;

wedge friction shoes cooperating with the.

wedge blocks; a spring resistance copperating with said friction shoes; longitudinally arranged friction plates adapted for relative movement upon relative movement of said follower casings, said plates being divided into two groups on opposite sides of said wedge pressure creating means, each group comprising two sets of plates; means movable with said friction shoes duringrelease Ofthe mechanism to engage each plate near one end thereof for restoring each set of plates to normal position with the last-named ends thereof slightly spaced fromythe adjacent follower; andnv friction elcinent having :in-

clined friction surfaces interposed between each group of'plates and the adjacent friction adapted to move relatively ;of a wedge'bloel: movable with each casing; friction shoes cooperating with each wedge'block; longitudinally arranged friction plates adapted for relative movement upon relative movement of thefollower casin said plates being dividcd into two lgroupsz'and disposed on op-' pesite sides of the friction shoes, each group con'iprising two sets of'plates; atapered fricion element interposed between each group of plates and. the adjacent friction surfaces of said casings;-a main spring resistance opposing relative approach of said friction shoes; and spring" followers interposed be tween saidspring resistanceand shoes,said spring; followers having means thereon for engaging; said plates and restoring'the same to nornial position after each compression stroke. Y i

8. In a friction shock absorbing- :mechanil the, combination with a1pair of chambered followers, the side walls of each being tapered of a centrally disposed wedgeiele mcnt carried by each follower; intercalate'd plates 'at opposite-sides of the mechanism, said plates being relatively movable :with reference to cachother byengagementwith said followers upon relative.approach ofthe latter; friction she-cs'co operating with said wedgin; elements and engaging: said plates for creating lateral pressureon said plates during compression of said gear; spring;' means opposing movement of said friction shoes, said spring means being compressed daring relative approach of the followers, and the: ansive action of mid s *inn' inc-ans effecting ,esi'o?ation of the plates to normal position during: release of the mechanism; and atapered plate interp' sod between the friction plates and the side walls of said chambered followers. l

9. In a friction shock absorbing mechanism, the combination with front and rear followers having opposed side walls provided with interior friction snrfaces, s'aid opposed interior surfaces eonvergino' outwardly of the mechanism; of'a plurality of intercalated friction plates, including a platehavinnsurfaces correspondingly inclined to said opposed inclined surfaces of the front and rear followers at one side of the mechanism and engaging the inclined surfaces of said lift) .llS

followers at the same side of the mechanism; means for creating lateral pressure on said plates, including front and rear Wedge blocks co-operating with said followers and friction shoes interposed between the wedge blocks and plates; and spring resistance means opposing relative movement of the friction shoes, said spring resistance means being compressed during relative approach during release of the mechanism efiecting restoration of the plates to normal position.

In witness that I claim the foregoing I have hereunto subscribed my name this 28th day 15 of January, 1927.

JOHN F. OCONNOR. 

